When the ios 8 upgrade notification popped up on my iphone 4s, it asked for almost 5GB of free space to install about 800mb of operating system. It took me a while to get 5 GB space but I did it after few weeks to deleting unnecessary apps and videos.

IOS 7 was working perfectly and everything was super fast. Apps would open right away and the responsiveness was just great.

Then i installed IOS8 and there was night and day of difference. Everything was slow. The responsiveness was not there. Sometimes it would take 10 seconds for the screen to acknowledge my touch. All apps are taking almost a minute before I can start using it. Even facebook app takes a while to load.

Let's trust these greedy tech companies to screw up a working product just because they need to sell their new phones.